▎ 摘　　要

NOVELTY - Preparing wafer-sized gallium oxide film comprises (1) cleaning gallium metal droplets to remove the surface oxide film to obtain pure gallium droplets, (2) placing the pure gallium droplet on the surface of the heated substrate, and roll the gallium droplet with an extrusion rod coated with a viscoelastic or rubbery polymer material on the surface, rolling at least one time to form a wafer-sized film with uniform thickness, and (3) annealing the thin film to obtain a gallium oxide film. USE - The method is useful for preparing wafer-sized gallium oxide film. ADVANTAGE - The film has stable quality and good continuity, and amorphous, polycrystalline or single crystal film can be obtained according to the requirement.